<!DOCTYPE html>
<html lang="zh_CN">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>小黑记事本</title>
</head>

<body>
    <!-- 主题区域 -->
    <section id="todoapp">
        <!-- 输入框 -->
        <header class="header">
            <h1>小黑记事本</h1>
            <input v-model="inputValue" @keyup.enter="add" autodocus="autofocus" autocomplete="off" placeholder="请输入任务"
                class="new-todo" />
        </header>
        <!-- 列表区域 -->
        <section class="main">
            <ul class="todo-list">
                <li class="todo" v-for="(item,index) in list">
                    <div class="view">
                        <span class="index">{{index+1}}.</span>
                        <label>{{item}}</label>
                        <button class="destory" @click="remove(index)"></button>
                    </div>
                </li>
            </ul>
        </section>
        <!-- 统计和清空 -->
        <footer class="footer">
            <span class="todo-count" v-if="list.length!=0">
                <strong>{{list.length}}</strong>items left
            </span>
            <button class="clear-completed" @click="clear" v-show="list.length!=0">
                Clear
            </button>
        </footer>
    </section>

    <!-- 开发环境版本 -->
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
        var app = new Vue({
            el: "#todoapp",
            data: {
                list: ["写代码", "吃饭饭", "打豆豆"],
                inputValue: "好好学习，天天向向上"
            },
            methods: {
                add: function () {
                    this.list.push(this.inputValue)
                },
                remove: function (index) {
                    // splice方法对应index删除元素
                    this.list.splice(index, 1);
                },
                clear: function () {
                    this.list = [];
                }
            }
        })
    </script>
</body>

</html>